[PATCH 6.19 394/781] PCI: endpoint: Add dynamic_inbound_mapping EPC feature

Greg Kroah-Hartman
2026-02-25T01:34:56Z

From: Koichiro Den <den@valinux.co.jp>

[ Upstream commit 06a81c5940e46cc7bddee28f16bdd29a12a76344 ]

Introduce a new EPC feature bit (dynamic_inbound_mapping) that indicates
whether an Endpoint Controller can update the inbound address
translation for a BAR without requiring the EPF driver to clear/reset
the BAR first.

Endpoint Function drivers (e.g. vNTB) can use this information to decide
whether it really is safe to call pci_epc_set_bar() multiple times to
update inbound mappings for the BAR.

Suggested-by: Niklas Cassel <cassel@kernel.org>
Signed-off-by: Koichiro Den <den@valinux.co.jp>
Signed-off-by: Manivannan Sadhasivam <mani@kernel.org>
Reviewed-by: Niklas Cassel <cassel@kernel.org>
Reviewed-by: Frank Li <Frank.Li@nxp.com>
Link: https://patch.msgid.link/20260124145012.2794108-2-den@valinux.co.jp
Stable-dep-of: 72cb5ed2a5c6 ("PCI: dwc: ep: Add per-PF BAR and inbound ATU mapping support")
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
include/linux/pci-epc.h | 5 +++++
1 file changed, 5 insertions(+)

diff --git a/include/linux/pci-epc.h b/include/linux/pci-epc.h
index 4286bfdbfdfad..4c8516756c568 100644
--- a/include/linux/pci-epc.h
+++ b/include/linux/pci-epc.h
@@ -223,6 +223,10 @@ struct pci_epc_bar_desc {
/**
* struct pci_epc_features - features supported by a EPC device per function
* @linkup_notifier: indicate if the EPC device can notify EPF driver on link up
+ * @dynamic_inbound_mapping: indicate if the EPC device supports updating
+ * inbound mappings for an already configured BAR
+ * (i.e. allow calling pci_epc_set_bar() again
+ * without first calling pci_epc_clear_bar())
* @msi_capable: indicate if the endpoint function has MSI capability
* @msix_capable: indicate if the endpoint function has MSI-X capability
* @intx_capable: indicate if the endpoint can raise INTx interrupts
@@ -231,6 +235,7 @@ struct pci_epc_bar_desc {
*/
struct pci_epc_features {
unsigned int linkup_notifier : 1;
+ unsigned int dynamic_inbound_mapping : 1;
unsigned int msi_capable : 1;
unsigned int msix_capable : 1;
unsigned int intx_capable : 1;
--
2.51.0